Consumers are always seeking high-quality comestibles that are easy to prepare and easy to eat. When such a product is easy to manufacture, costs may also be low for this product. In the case of bread-like products, the bread portion of the product should have appropriate volume, crumb texture, and mouthfeel. The texture of the product should not be too chewy or tough, and the crust should preferably be brown and have the proper texture.
Extrusion processes have been used for the formation of certain dough products. The extrusion process offers an efficient and cost-effective approach for the formation of both cooked and uncooked products. Uncooked extrusion products are prepared by a cold extrusion method, and the resulting products typically are cooked either by the manufacturer or the consumer. Perhaps the most common example of an uncooked or raw extrusion product is pasta. In the past, cold extrusion processes have been used to make dense products. This type of product is a natural outcome of extrusion processes, because extrusion operates by pushing the ingredients, often under significant pressure, up to and through a die. This high-pressure generally causes a composition to release any trapped gases present in the composition. Due to this degassing, an extruded composition generally has fewer air-containing pockets than it did before the extrusion process. This is problematic if the product being extruded is intended to be a bread-like product. Thus, breads made by an extrusion process using previously known techniques generally have a less desirable texture than like breads that are not made by an extrusion process.
Because of high pressures during extrusion, extruding is generally not suited for producing open celled or high specific volume bread-like doughs or dough-products because the die pressure can cause significant shear, degassing, and tearing to the cellular structure which holds trapped gases. Bread-like products that have been extruded generally appear translucent because little or no air is trapped in the cell walls. Such products are generally denser than desired.
U.S. Pat. No. 6,180,151 to Geng, et al. describes a method of extruding dough products at a temperature less than about 145° F. The dough contains a chemical leavener system that releases carbon dioxide from the formation of the mixture through the extrusion to decrease the density of the extruded dough by at least about 5 percent relative to the corresponding extruded dough without the chemical leavener. The temperature of extrusion is identified as being at a temperature that does not cook or gelatinize the starch within the dough. See column three, lines 1-4. The resulting product has texture approximating pie crust. See column three, line 14.
U.S. Pat. No. 6,068,863 to Dupart, et al. discloses bread products prepared by treating a starch material in water with carbohydrase, so that the starch material is gelatinized. This gelatinized starch is combined with water, a starch material, a vegetable oil and lecithin so that an emulsion is obtained. The emulsion is heated to gelatinize the starch and then dried to obtain a powder. The powder is combined by mixing with wheat flour, sugar, raising agent and water to obtain a dough. The dough may be stored at low temperature or baked. This product is stated to be microwavable.
U.S. Pat. No. 5,049,398 to Saari et al. discloses a method of baking microwave bread. The dough as described therein is made by first prehydrating a defined dough conditioner system and pregelatinized starch to form an emulsion, combining the emulsion with the other ingredients by admixing to form a dough and finish preparing the dough to produce a finished microwave baked bread loaf. See the abstract. The pregelatinized starch component is stated to be provided in an effective amount to improve the table life of the food product upon exposure to microwave heating. See column three, lines 19-22.